Topographic effects on crustal stress around the Atera Fault, central Japan

Abstract

The stress estimated from hydraulic fracturing test was inconsistent with a centroid moment tensor inversion result at the Atera fault area, Gifu Prefecture, central Japan. We demonstrate the stress obtained from a hydraulic fracturing mainly reflects topographic effect. We conduct a numeral computation of topographic stress using a formulation of the Boussinesq problem. The calculated maximum compression stress directions are consistent with the in situ measurement at the hydraulic fracturing depth. The results demonstrate the importance of topographic effects on crustal stress at a shallow depth.[Figure not available: see fulltext.]